Malicious PDF — malware analysis report

Static analysis result for SHA-256 7853b59f297e1f78…

MALICIOUS

PDF

38.0 KB Created: 2020-08-25 00:19:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 38c87d66d88857e8f49737cd1e2c4bc3 SHA-1: b426f5f618ca68d5a9f57f7d1fd44beffddfe593 SHA-256: 7853b59f297e1f787cf6e8074a29f5b44e141b92ae73361f7c23ede987d96062
162 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains embedded links that redirect to malicious infrastructure, specifically identified as a redirector for 'ielts listening test 4 section 3 answers'. The ML classifier strongly indicates maliciousness, and the presence of a download button lure reinforces the deceptive nature of the document. The document's primary function appears to be to trick users into visiting a malicious URL.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/pify?keyword=ielts+listening+test+4+section+3+answers
    • http://wivupi.barbarayontzatstac.com/uploads/1/3/0/8/130814124/aa46e80b.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/5005/7373/files/al_azkar_imam_nawawi_download.pdf
    • https://cdn.shopify.com/s/files/1/0433/9384/3358/files/jeburizojezipu.pdf
    • https://cdn.shopify.com/s/files/1/0435/3572/8794/files/calligraphy_letters_fonts_free.pdf
    • https://cdn.shopify.com/s/files/1/0430/2353/2195/files/mazinger_z_wallpaper_android.pdf
    • https://cdn.shopify.com/s/files/1/0430/8615/1834/files/31815303953.pdf
    • https://cdn.shopify.com/s/files/1/0432/5274/4356/files/jepaziki.pdf
    • https://cdn.shopify.com/s/files/1/0429/1543/0553/files/18341295035.pdf
    • https://cdn.shopify.com/s/files/1/0430/7235/6509/files/didigexesexidiwufub.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000056e5.bin
cce21418d5df8c3d0c7f838339f329ee4ba67865b8cc1d8973829d8d27cabade
pdf-font-stream PDF embedded font (sfnt) at offset 0x56E5 5248 bytes
font_01_sfnt_off000068e1.bin
0c864e10296e02a3b8814c984eb681fe23f2c0b4e3769168d96696432a25fdf5
pdf-font-stream PDF embedded font (sfnt) at offset 0x68E1 10288 bytes